Source for javax.swing.plaf.basic.SharedUIDefaults

   1: /* SharedUIDefaults.java -- Manages shared instances for UIDefaults
   2:    Copyright (C) 2006 Free Software Foundation, Inc.
   3: 
   4: This file is part of GNU Classpath.
   5: 
   6: GNU Classpath is free software; you can redistribute it and/or modify
   7: it under the terms of the GNU General Public License as published by
   8: the Free Software Foundation; either version 2, or (at your option)
   9: any later version.
  10: 
  11: GNU Classpath is distributed in the hope that it will be useful, but
  12: WITHOUT ANY WARRANTY; without even the implied warranty of
  13: MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14: General Public License for more details.
  15: 
  16: You should have received a copy of the GNU General Public License
  17: along with GNU Classpath; see the file COPYING.  If not, write to the
  18: Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  19: 02110-1301 USA.
  20: 
  21: Linking this library statically or dynamically with other modules is
  22: making a combined work based on this library.  Thus, the terms and
  23: conditions of the GNU General Public License cover the whole
  24: combination.
  25: 
  26: As a special exception, the copyright holders of this library give you
  27: permission to link this library with independent modules to produce an
  28: executable, regardless of the license terms of these independent
  29: modules, and to copy and distribute the resulting executable under
  30: terms of your choice, provided that you also meet, for each linked
  31: independent module, the terms and conditions of the license of that
  32: module.  An independent module is a module which is not derived from
  33: or based on this library.  If you modify this library, you may extend
  34: this exception to your version of the library, but you are not
  35: obligated to do so.  If you do not wish to do so, delete this
  36: exception statement from your version. */
  37: 
  38: 
  39: package javax.swing.plaf.basic;
  40: 
  41: import java.util.HashMap;
  42: 
  43: import javax.swing.UIManager;
  44: 
  45: /**
  46:  * Manages shared instances for UI defaults. For example, all Swing components
  47:  * of one type usually share one InputMap/ActionMap pair. In order to avoid
  48:  * duplication of such objects we store them in a Map here.
  49:  *
  50:  * @author Roman Kennke (kennke@aicas.com)
  51:  */
  52: public class SharedUIDefaults
  53: {
  54: 
  55:   /**
  56:    * Stores the shared instances, indexed by their UI names
  57:    * (i.e. "TextField.InputMap").
  58:    */
  59:   private static HashMap sharedDefaults = new HashMap();
  60: 
  61:   /**
  62:    * Returns a shared UI defaults object.
  63:    *
  64:    * @param key the key for the shared object
  65:    *
  66:    * @return a shared UI defaults object for the specified key
  67:    */
  68:   static Object get(String key)
  69:   {
  70:     Object o = sharedDefaults.get(key);
  71:     if (o == null)
  72:       {
  73:         o = UIManager.get(key);
  74:         sharedDefaults.put(key, o);
  75:       }
  76:     return o;
  77:   }
  78: }